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Invasive Species in Yosemite

Cara Brook investigated the invasion of the non-native common raven in the Yosemite National Park ecosystem.  Her research sought to connect the invasion with National Park Service policy and increased anthropogenic activity. She conducted bird count transects in the park, which revealed that the raven is most densely distributed in human-populated regions of Yosemite. She later conducted time-series studies, which tracked the movement of ravens throughout the park in response to the availability of human food.  Her research tracked the birds over the course of a single day and across an entire season. Cara suggested that a combination of heightened visitation following World War II and National Park Service development projects created an environment rich in human food sources. The availability of food encouraged the invasion of the raven. Cara used her research to write an honors thesis with Stanford's Goldman Interschool Honors Program in Environmental Science, Technology, and Policy.